It may be a feature but it looks like a bug to me:
Eigenvalues[mat] does not return the list in the same order as
Eigensystem[mat][[1]]
This change in order means that the result of Eigenvalues[] cannot be
used together with Eigenvectors[] i.e.
mat.Transpose[Eigenvectors[mat]] !=
Transpose[Eigenvectors[mat]].DiagonalMatrix[Eigenvalues[mat]]
Eigensystem[] is internally consistent.
Bill
________________________________________________________________
Bill Lytton billl at helmholtz.sdsc.edu
Salk Institute tel 619 453 4100 x124
10010 N. Torrey Pines Rd. fax 619 587 0417
La Jolla, CA 92037
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